I don't use iTerm2, but I have a global hide/show shortcut via Hammerspoon (https://github.com/cweagans/dotfiles/blob/90764db6146383a92e...). I could extend this to pretty much any app, but the only one I regularly need it for is my terminal.

I like this method a little more because it's not a single session, there's no animation, etc. It just pops into existence exactly how/where I left it, and then goes away again when I'm done with it.